同源重组缺陷检测在乳腺癌个体化治疗中的应用价值

Objective To assess the application of homologous recombination deficiency (HRD) detection in breast cancer diagnosis and treatment at The First Affiliated Hospital of Xi'an Jiaotong University, and to analyze the clinicopathological features of HRD-positive breast cancer patients and explore the role of HRD testing in guiding treatment decisions. Methods For this retrospective cohort study, we collected complete clinicopathological data and genetic testing reports of breast cancer patients who underwent HRD detection at The First Affiliated Hospital of Xi'an Jiaotong University from October 2021 to May 2024. Patients were classified into HRD-positive and HRDnegative groups based on their test results. Differences in clinicopathological characteristics and changes in clinical decision-making before and after HRD testing were analyzed to assess the clinical utility of HRD testing in guiding individualized treatment strategies. Results This study included a total of 127 breast cancer patients, of whom the HRD positive detection rate was 54.3%(69/127). The proportion of estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, human epidermal growth factor receptor 2 (HER2)-negative and triple-negative breast cancer (72.5% vs. 43.1%) with histological grade 3 (50.7% vs. 20.7%) was significantly higher in HRD-positive patients than in HRD-negative patients (P<0.05). Clinical decision analysis revealed that HRD testing results significantly affected preoperative neoadjuvant therapy selection (McNemar test, P=0.015) and the postoperative use of platinum-based chemotherapy and poly (ADP-ribose) polymerase inhibitor (PARPi) (McNemar test, P< 0.001). Multivariate Logistic regression identified histological grade 3 as an independent risk factor for HRD positivity (OR=3.97, 95% CI: 1.70-9.26, P=0.001), while PR positivity (OR=0.35, 95% CI: 0.15-0.79, P=0.012) and low HER2 expression (OR=0.40, 95% CI: 0.18-0.91, P=0.028) were protective factors. Conclusion HRD-positive patients mainly present with negative expressions of ER, PR, and HER2, accompanied by high expression of Ki-67 and high histological grade. HRD detection can provide important reference for clinical decision-making in breast cancer patients, especially in selection and application of platinum chemotherapy drugs and PARPi. Histological grade, PR status and HER2 status are independent predictors of HRD positivity.